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1.
Res Sq ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38463967

RESUMO

Metal ions are vital components in many proteins for the inference and engineering of protein function, with coordination complexity linked to structural (4-residue predominate), catalytic (3-residue predominate), or regulatory (2-residue predominate) roles. Computational tools for modeling metal ions in protein structures, especially for transient, reversible, and concentration-dependent regulatory sites, remain immature. We present PinMyMetal (PMM), a sophisticated hybrid machine learning system for predicting zinc ion localization and environment in macromolecular structures. Compared to other predictors, PMM excels in predicting regulatory sites (median deviation of 0.34 Å), demonstrating superior accuracy in locating catalytic sites (median deviation of 0.27 Å) and structural sites (median deviation of 0.14 Å). PMM assigns a certainty score to each predicted site based on local structural and physicochemical features independent of homolog presence. Interactive validation through our server, CheckMyMetal, expands PMM's scope, enabling it to pinpoint and validates diverse functional zinc sites from different structure sources (predicted structures, cryo-EM and crystallography). This facilitates residue-wise assessment and robust metal binding site design. The lightweight PMM system demands minimal computing resources and is available at https://PMM.biocloud.top. While currently trained on zinc, the PMM workflow can easily adapt to other metals through expanded training data.

2.
BMC Plant Biol ; 24(1): 174, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38443815

RESUMO

BACKGROUND: The N-terminal regulatory element (NRE) of Receptor-like kinases (RLKs), consisting of the juxtamembrane segment in receptor kinases (RKs) and the N-terminal extension segment in RLCKs, is a crucial component that regulates the activities of these proteins. However, the features and functions of the NRE have remained largely unexplored. Herein, we comprehensively analyze 510,233 NRE sequences in RLKs from 528 plant species, using information theory and data mining techniques to unravel their common characteristics and diversity. We also use recombinant RKs to investigate the function of the NRE in vitro. RESULTS: Our findings indicate that the majority of NRE segments are around 40-80 amino acids in length and feature a serine-rich region and a 14-amino-acid consensus sequence, 'FSYEELEKAT[D/N]NF[S/D]', which contains a characteristic α-helix and ST motif that connects to the core kinase domain. This conserved signature sequence is capable of suppressing FERONIA's kinase activity. A motif discovery algorithm identifies 29 motifs with highly conserved phosphorylation sites in RK and RLCK classes, especially the motif 'VGPWKpTGLpSGQLQKAFVTGVP' in LRR-VI-2 class. Phosphorylation of an NRE motif in an LRR-VI-2 member, MDIS1, modulates the auto-phosphorylation of its co-receptor, MIK1, indicating the potential role of NRE as a 'kinase switch' in RLK activation. Furthermore, the characterization of phosphorylatable NRE motifs improves the accuracy of predicting phosphorylatable sites. CONCLUSIONS: Our study provides a comprehensive dataset to investigate NRE segments from individual RLKs and enhances our understanding of the underlying mechanisms of RLK signal transduction and kinase activation processes in plant adaptation.


Assuntos
Algoritmos , Aminoácidos , Fosforilação , Sequência de Aminoácidos , Membrana Celular
3.
Mol Plant ; 17(4): 658-671, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38384130

RESUMO

Receptor-like kinases (RLKs) are the most numerous signal transduction components in plants and play important roles in determining how different plants adapt to their ecological environments. Research on RLKs has focused mainly on a small number of typical RLK members in a few model plants. There is an urgent need to study the composition, distribution, and evolution of RLKs at the holistic level to increase our understanding of how RLKs assist in the ecological adaptations of different plant species. In this study, we collected the genome assemblies of 528 plant species and constructed an RLK dataset. Using this dataset, we identified and characterized 524 948 RLK family members. Each member underwent systematic topological classification and was assigned a gene ID based on a unified nomenclature system. Furthermore, we identified two novel extracellular domains in some RLKs, designated Xiao and Xiang. Evolutionary analysis of the RLK family revealed that the RLCK-XVII and RLCK-XII-2 classes were present exclusively in dicots, suggesting that diversification of RLKs between monocots and dicots may have led to differences in downstream cytoplasmic responses. We also used an interaction proteome to help empower data mining for inference of new RLK functions from a global perspective, with the ultimate goal of understanding how RLKs shape the adaptation of different plants to the environments/ecosystems. The assembled RLK dataset, together with annotations and analytical tools, forms an integrated foundation of multiomics data that is publicly accessible via the metaRLK web portal (http://metaRLK.biocloud.top).


Assuntos
Proteínas de Plantas , Proteínas Serina-Treonina Quinases , Proteínas Serina-Treonina Quinases/genética , Proteínas de Plantas/genética , Ecossistema , Plantas/genética , Proteínas Quinases/genética , Filogenia
4.
Int J Antimicrob Agents ; 63(4): 107101, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38325722

RESUMO

BACKGROUND: Resistance to extended-spectrum cephalosporins (ESCs) has become a public health concern with the spread of Neisseria gonorrhoeae and increasing antimicrobial resistance. Mutation of penA, encoding penicillin-binding protein 2, represents a mechanism of ESC resistance. This study sought to assess penA alleles and mutations associated with decreased susceptibility (DS) to ESCs in N. gonorrhoeae. MATERIALS AND METHODS: In 2021, 347 gonococci were collected in Guangdong, China. Minimum inhibitory concentations (MICs) of ceftriaxone and cefixime were determined, and whole-genome sequencing and phylogenetic analysis were performed. Multi-locus sequence typing (MLST) and conventional resistance determinants such as penA, mtrR, PonA and PorB were analysed. penA was genotyped and sequence-aligned using PubMLST. RESULTS: Genome-wide phylogenetic analysis revealed that the prevalence of DS to ESCs was highest in Clade 11.1 (100.0%), Clade 2 (66.7%) and Clade 0 (55.7%), and the leading cause was strains with penA-60.001 or new penA alleles in clades. The penA phylogenetic tree is divided into two branches: non-mosaic penA and mosaic penA. The latter contained penA-60.001, penA-10 and penA-34. penA profile analysis indicated that A311V and T483S are closely related to DS to ESCs in mosaic penA. The new alleles NEIS1753_2840 and NEIS1753_2837 are closely related to penA-60.001, with DS to ceftriaxone and cefixime of 100%. NEIS1753_2660, a derivative of penA-10 (A486V), has increased DS to ceftriaxone. NEIS1753_2846, a derivative of penA-34.007 (G546S), has increased DS to cefixime. CONCLUSION: This study identified critical penA alleles related to elevated MICs, and trends of gonococcus-evolved mutated penA associated with DS to ESCs in Guangdong.


Assuntos
Ceftriaxona , Gonorreia , Humanos , Ceftriaxona/farmacologia , Cefixima/farmacologia , Neisseria gonorrhoeae/genética , Antibacterianos/farmacologia , Tipagem de Sequências Multilocus , Alelos , Filogenia , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Testes de Sensibilidade Microbiana , Cefalosporinas/farmacologia , China/epidemiologia
5.
Plant Cell ; 36(4): 919-940, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38180963

RESUMO

Soil salinity results in oxidative stress and heavy losses to crop production. The S-acylated protein SALT TOLERANCE RECEPTOR-LIKE CYTOPLASMIC KINASE 1 (STRK1) phosphorylates and activates CATALASE C (CatC) to improve rice (Oryza sativa L.) salt tolerance, but the molecular mechanism underlying its S-acylation involved in salt signal transduction awaits elucidation. Here, we show that the DHHC-type zinc finger protein DHHC09 S-acylates STRK1 at Cys5, Cys10, and Cys14 and promotes salt and oxidative stress tolerance by enhancing rice H2O2-scavenging capacity. This modification determines STRK1 targeting to the plasma membrane or lipid nanodomains and is required for its function. DHHC09 promotes salt signaling from STRK1 to CatC via transphosphorylation, and its deficiency impairs salt signal transduction. Our findings demonstrate that DHHC09 S-acylates and anchors STRK1 to the plasma membrane to promote salt signaling from STRK1 to CatC, thereby regulating H2O2 homeostasis and improving salt stress tolerance in rice. Moreover, overexpression of DHHC09 in rice mitigates grain yield loss under salt stress. Together, these results shed light on the mechanism underlying the role of S-acylation in RLK/RLCK-mediated salt signal transduction and provide a strategy for breeding highly salt-tolerant rice.


Assuntos
Oryza , Tolerância ao Sal , Tolerância ao Sal/genética , Oryza/metabolismo , Peróxido de Hidrogênio/metabolismo , Homeostase , Dedos de Zinco , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
6.
iScience ; 27(1): 108581, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38213624

RESUMO

Prompt diagnosis is essential for managing herpes simplex virus types 1 and 2 (HSV-1/2). Existing diagnostic methods are not widely available that required expensive or additional equipment for conducting examinations and result readouts, which can limit their utility in resource-constrained settings. We successfully developed a CRISPR-Cas13a-based assay for the detection and genotyping of HSV. Our assay demonstrated a high sensitivity of 96.15% and 95.15% for HSV-1 and HSV-2, respectively, with a specificity of 100% compared to a commercial qPCR assay when tested on 194 clinical samples. Remarkably, the assay enables a limit of detection of 1 copy/µL of viral DNA, facilitated by an enhanced input of RPA product and is designed for both mobile app integration and colorimetric interpretation, allowing for semiquantitative readings. These findings highlight the excellent performance of our CRISPR-based diagnostic in detecting HSV and its potential for point-of-care testing in resource-constrained settings.

7.
Heliyon ; 9(11): e22302, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38053876

RESUMO

Acute respiratory tract infections (ARTI) are caused by respiratory pathogens and range from asymptomatic infections to severe respiratory diseases. These diseases can be life threatening with high morbidity and mortality worldwide. Under the pandemic of coronavirus disease 2019 (COVID-19), little has been reported about the pathogen etiologies and epidemiology of patients suffering from ARTI of all age in Xiamen. Region-specific surveillance in individuals with ARTI of all ages was performed in Xiamen from January 2020 to October 2022. Here, we observed the epidemiological characteristics of thirteen pathogens within ARTI patients and further revealed the difference of that between upper respiratory tract infections (URTI) and lower respiratory tract infections (LRTI). In total 56.36 % (2358/4184) of the ARTI patients were positive for at least one respiratory pathogen. Rhinovirus (RVs, 29.22 %), influenza A (FluA, 19.59 %), respiratory syncytial virus (RSV, 18.36 %), metapneumovirus (MPV, 13.91 %), and adenovirus (ADV, 10.31 %) were the five leading respiratory pathogens. Respiratory pathogens displayed age- and season-specific patterns, even between URTI and LRTI. Compared with other groups, a higher proportion of FluA (52.17 % and 68.75 %, respectively) infection was found in the adult group and the elder group, while the lower proportion of RVs (14.11 % and 11.11 %) infection was also observed in them. Although ARTI cases circulated throughout the year, RVs, FluB, and BoV peaked in autumn, and FluA circulated more in summer. Besides, the co-infectious rate was 8.7 % with the most common for RVs. Logistic regression analyses revealed the correlations between respiratory pathogens and disease types. These results are essential for replenishing epidemiological characteristics of common respiratory pathogens that caused ARTI in Xiamen during the epidemic of COVID-19, and a better understanding of it might optimize the local prevention and clinical control.

8.
medRxiv ; 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37905017

RESUMO

Background: The global resurgence of syphilis requires novel prevention strategies. Whole genome sequencing (WGS) of Treponema pallidum ( TPA ) using different specimen types is essential for vaccine development. Methods: Patients with primary (PS) and secondary (SS) syphilis were recruited in Guangzhou, China. We collected ulcer exudates and blood from PS participants, and skin biopsies and blood from SS participants for TPA polA polymerase chain reaction (PCR); ulcer exudates and blood were also used to isolate TPA strains by rabbit infectivity testing (RIT). TPA WGS was performed on 52 ulcer exudates and biopsy specimens and 25 matched rabbit isolates. Results: We enrolled 18 PS and 51 SS participants from December 2019 to March 2022. Among PS participants, TPA DNA was detected in 16 (89%) ulcer exudates and three (17%) blood specimens. Among SS participants, TPA DNA was detected in 50 (98%) skin biopsies and 27 (53%) blood specimens. TP A was isolated from 48 rabbits, with a 71% (12/17) success rate from ulcer exudates and 69% (36/52) from SS bloods. Twenty-three matched SS14 clade genomes were virtually identical, while two Nichols clade pairs had discordant tprK sequences. Forty-two of 52 unique TPA genomes clustered in an SS14 East Asia subgroup, while ten fell into two East Asian Nichols subgroups. Conclusions: Our TPA detection rate was high from PS ulcer exudates and SS skin biopsies and over 50% from SS whole blood, with RIT isolation in over two-thirds of samples. Our results support the use of WGS from rabbit isolates to inform vaccine development. Summary: We performed Treponema pallidum molecular detection and genome sequencing from multiple specimens collected from early syphilis patients and isolates obtained by rabbit inoculation. Our results support the use of whole genome sequencing from rabbit isolates to inform syphilis vaccine development.

9.
Microbiol Spectr ; 11(6): e0046423, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37882532

RESUMO

IMPORTANCE: A method for Neisseria gonorrhoeae (NG)/Chlamydia trachomatis (CT) detection is developed using multiplex-recombinase polymerase amplification and Cas12a/Cas13a. This method can detect NG and CT simultaneously with high sensitivity and specificity. This method has great potential to be further developed into larger-scale screening and point-of-care testing (POCT).


Assuntos
Infecções por Chlamydia , Gonorreia , Humanos , Neisseria gonorrhoeae/genética , Chlamydia trachomatis/genética , Gonorreia/diagnóstico , Infecções por Chlamydia/diagnóstico , Sensibilidade e Especificidade
10.
medRxiv ; 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37546832

RESUMO

Background: The continuing increase in syphilis rates worldwide necessitates development of a vaccine with global efficacy. We conducted a multi-center, observational study to explore Treponema pallidum subsp. pallidum ( TPA ) molecular epidemiology essential for vaccine research by analyzing clinical data and specimens from early syphilis patients using whole-genome sequencing (WGS) and publicly available WGS data. Methods: We enrolled patients with primary (PS), secondary (SS) or early latent (ELS) syphilis from clinics in China, Colombia, Malawi and the United States between November 2019 - May 2022. Inclusion criteria included age ≥18 years, and syphilis confirmation by direct detection methods and/or serological testing. TPA detection and WGS were conducted on lesion swabs, skin biopsies/scrapings, whole blood, and/or rabbit-passaged isolates. We compared our WGS data to publicly available genomes, and analysed TPA populations to identify mutations associated with lineage and geography. Findings: We screened 2,820 patients and enrolled 233 participants - 77 (33%) with PS, 154 (66%) with SS, and two (1%) with ELS. Median age of participants was 28; 66% were cis -gender male, of which 43% reported identifying as "gay", "bisexual", or "other sexuality". Among all participants, 56 (24%) had HIV co-infection. WGS data from 113 participants demonstrated a predominance of SS14-lineage strains with geographic clustering. Phylogenomic analysis confirmed that Nichols-lineage strains are more genetically diverse than SS14-lineage strains and cluster into more distinct subclades. Differences in single nucleotide variants (SNVs) were evident by TPA lineage and geography. Mapping of highly differentiated SNVs to three-dimensional protein models demonstrated population-specific substitutions, some in outer membrane proteins (OMPs) of interest. Interpretation: Our study involving participants from four countries substantiates the global diversity of TPA strains. Additional analyses to explore TPA OMP variability within strains will be vital for vaccine development and improved understanding of syphilis pathogenesis on a population level. Funding: National Institutes of Health, Bill and Melinda Gates Foundation.

11.
Cell Rep ; 42(7): 112766, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37421618

RESUMO

Neuraminidase is suggested as an important component for developing a universal influenza vaccine. Targeted induction of neuraminidase-specific broadly protective antibodies by vaccinations is challenging. To overcome this, we rationally select the highly conserved peptides from the consensus amino acid sequence of the globular head domains of neuraminidase. Inspired by the B cell receptor evolution process, a reliable sequential immunization regimen is designed to result in immuno-focusing by steering bulk immune responses to a selected region where broadly protective B lymphocyte epitopes reside. After priming neuraminidase protein-specific antibody responses in C57BL/6 or BALB/c inbred mice strains by immunization or pre-infection, boost immunizations with certain neuraminidase-derived peptide-keyhole limpet hemocyanin conjugates significantly strengthened serum neuraminidase inhibition activities and cross-protections. Overall, this study provides proof of concept for a peptide-based sequential immunization strategy for achieving targeted induction of cross-protective antibody response, which provides references for designing universal vaccines against other highly variable pathogens.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Virus da Influenza A Subtipo H5N1 , Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Animais , Camundongos , Humanos , Infecções por Orthomyxoviridae/prevenção & controle , Neuraminidase , Anticorpos Antivirais , Camundongos Endogâmicos C57BL , Vacinação , Peptídeos , Camundongos Endogâmicos BALB C , Glicoproteínas de Hemaglutininação de Vírus da Influenza
12.
Front Physiol ; 14: 1176998, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37378075

RESUMO

The frequency of exertional heat stroke (EHS) increases with the gradual elevation of global temperatures during summer. Acute kidney injury (AKI) is a common complication of EHS, and its occurrence often indicates the worsening of a patient's condition or a poor prognosis. In this study, a rat model of AKI caused by EHS was established, and the reliability of the model was evaluated by HE staining and biochemical assays. The expression of kidney tissue proteins in the EHS rats was analyzed using label-free liquid chromatography-tandem mass spectrometry. A total of 3,129 differentially expressed proteins (DEPs) were obtained, and 10 key proteins were finally identified, which included three upregulated proteins (Ahsg, Bpgm, and Litaf) and seven downregulated proteins (medium-chain acyl-CoA synthetase 2 (Acsm2), Hadha, Keg1, Sh3glb1, Eif3d, Ambp, and Ddah2). The qPCR technique was used to validate these 10 potential biomarkers in rat kidney and urine. In addition, Acsm2 and Ahsg were double-validated by Western blotting. Overall, this study identified 10 reliable biomarkers that may provide potential targets for the treatment of AKI caused by EHS.

13.
Plant Cell ; 35(9): 3604-3625, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37325884

RESUMO

Catalase (CAT) is often phosphorylated and activated by protein kinases to maintain hydrogen peroxide (H2O2) homeostasis and protect cells against stresses, but whether and how CAT is switched off by protein phosphatases remains inconclusive. Here, we identified a manganese (Mn2+)-dependent protein phosphatase, which we named PHOSPHATASE OF CATALASE 1 (PC1), from rice (Oryza sativa L.) that negatively regulates salt and oxidative stress tolerance. PC1 specifically dephosphorylates CatC at Ser-9 to inhibit its tetramerization and thus activity in the peroxisome. PC1 overexpressing lines exhibited hypersensitivity to salt and oxidative stresses with a lower phospho-serine level of CATs. Phosphatase activity and seminal root growth assays indicated that PC1 promotes growth and plays a vital role during the transition from salt stress to normal growth conditions. Our findings demonstrate that PC1 acts as a molecular switch to dephosphorylate and deactivate CatC and negatively regulate H2O2 homeostasis and salt tolerance in rice. Moreover, knockout of PC1 not only improved H2O2-scavenging capacity and salt tolerance but also limited rice grain yield loss under salt stress conditions. Together, these results shed light on the mechanisms that switch off CAT and provide a strategy for breeding highly salt-tolerant rice.


Assuntos
Oryza , Catalase/genética , Catalase/metabolismo , Oryza/metabolismo , Peróxido de Hidrogênio/metabolismo , Proteína Fosfatase 1/metabolismo , Tolerância ao Sal/genética , Homeostase , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
14.
BMC Public Health ; 23(1): 1182, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37337181

RESUMO

BACKGROUND: Gonorrhea and chlamydia are the most common sexually transmitted diseases (STDs) among men who have sex with men (MSM) in China. Previous studies have shown pay-it-forward (PIF) interventions to be associated with a substantial increase in gonorrhea and chlamydia test uptake compared to standard-of-care. We propose a 'pay-it-forward' gonorrhea and chlamydia testing randomized controlled trial (PIONEER). The trial would evaluate the effectiveness of two pay-it-forward strategies in promoting testing uptake compared to the standard of care (in which men pay for their tests out-of-pocket) among MSM and male STD patients in China. METHODS: PIONEER will be a three-armed, pragmatic cluster randomized controlled trial (RCT), conducted across 12 clinics (six MSM-led and six public STD clinics) to compare the effectiveness of three implementation strategies. Each facility will be randomized to a standard pay-it-forward intervention of gonorrhea/ chlamydia testing with minimal encouragement for testing, a community-engaged pay-it-forward arm, or a control arm where men pay for their tests out-of-pockets. The primary outcome will be dual gonorrhea/chlamydia test uptake. Secondary outcomes will include syphilis testing, amount donated in pay-it-forward, number of positive gonorrhea and chlamydia tests, and measures of antimicrobial resistance. A sequential transformative mixed methods design will be used to evaluate the implementation process in type 2 effectiveness-implementation hybrid design. Data sources will include survey on acceptability, and feelings and attitudes towards the interventions among participants; testing and treatment uptake data from clinic records, WeChat records, and qualitative data to gain insights into men's perceptions and attitudes towards the pay-it-forward, mechanisms driving uptake, and donating behaviors. Implementers and organizers will be interviewed about fidelity and adherence to protocol, sustainability of pay-it-forward intervention, and barriers and facilitators of implementing the intervention. DISCUSSION: PIONEER will substantially increase gonorrhea/chlamydia testing among MSM in China, providing an innovative and new financial mechanism to sustain STD screening among sexual minorities in low- and middle-income countries. This study will answer compelling scientific questions about how best to implement pay-it-forward and the individual and organizational characteristics that moderate it. TRIAL REGISTRATION: The study with identification number NCT05723263 has been registered on clinicaltrials.gov/.


Assuntos
Infecções por Chlamydia , Chlamydia , Gonorreia , Infecções por HIV , Minorias Sexuais e de Gênero , Infecções Sexualmente Transmissíveis , Masculino , Humanos , Gonorreia/diagnóstico , Homossexualidade Masculina , Infecções Sexualmente Transmissíveis/diagnóstico , China/epidemiologia , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Infecções por HIV/diagnóstico , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Microbiol Spectr ; 11(3): e0482422, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37154721

RESUMO

Endophytes play an important role in shaping plant growth and immunity. However, the mechanisms for endophyte-induced disease resistance in host plants remain unclear. Here, we screened and isolated the immunity inducer ShAM1 from the endophyte Streptomyces hygroscopicus OsiSh-2, which strongly antagonizes the pathogen Magnaporthe oryzae. Recombinant ShAM1 can trigger rice immune responses and induce hypersensitive responses in various plant species. After infection with M. oryzae, blast resistance was dramatically improved in ShAM1-inoculated rice. In addition, the enhanced disease resistance by ShAM1 was found to occur through a priming strategy and was mainly regulated through the jasmonic acid-ethylene (JA/ET)-dependent signaling pathway. ShAM1 was identified as a novel α-mannosidase, and its induction of immunity is dependent on its enzyme activity. When we incubated ShAM1 with isolated rice cell walls, the release of oligosaccharides was observed. Notably, extracts from the ShAM1-digested cell wall can enhance the disease resistance of the host rice. These results indicated that ShAM1 triggered immune defense against pathogens by damage-associated molecular pattern (DAMP)-related mechanisms. Our work provides a representative example of endophyte-mediated modulation of disease resistance in host plants. The effects of ShAM1 indicate the promise of using active components from endophytes as plant defense elicitors for the management of plant disease. IMPORTANCE The specific biological niche inside host plants allows endophytes to regulate plant disease resistance effectively. However, there have been few reports on the role of active metabolites from endophytes in inducing host disease resistance. In this study, we demonstrated that an identified α-mannosidase protein, ShAM1, secreted by the endophyte S. hygroscopicus OsiSh-2 could activate typical plant immunity responses and induce a timely and cost-efficient priming defense against the pathogen M. oryzae in rice. Importantly, we revealed that ShAM1 enhanced plant disease resistance through its hydrolytic enzyme (HE) activity to digest the rice cell wall and release damage-associated molecular patterns. Taken together, these findings provide an example of the interaction mode of endophyte-plant symbionts and suggest that HEs derived from endophytes can be used as environmentally friendly and safe prevention agent for plant disease control.


Assuntos
Magnaporthe , Oryza , Resistência à Doença , Endófitos/fisiologia , alfa-Manosidase/metabolismo , alfa-Manosidase/farmacologia , Magnaporthe/metabolismo , Doenças das Plantas , Parede Celular
16.
ACS Omega ; 8(18): 16016-16031, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37179597

RESUMO

The application of silane in sulfoaluminate cement repair materials can improve its waterproof, permeability, freeze-thaw, and other properties, but it would reduce the mechanical properties of sulfoaluminate cement-based materials, making it unable to better meet the engineering requirements and durability indices. The modification of silane with graphene oxide (GO) can effectively address this issue. However, the failure mechanism of the interface between silane and sulfoaluminate cement-based materials and the modification mechanism of GO remain unclear. In this paper, the interface-bonding mechanical models of isobutyltriethoxysilane (IBTS)/ettringite and GO-IBTS/ettringite are established by molecular dynamics method to study the source of interface-bonding properties of IBTS, GO-IBTS, and ettringite, as well as the failure mechanism of interface bonding, to reveal the mechanism of GO-modifying IBTS to improve the interface-bonding properties of IBTS and ettringite. This study finds that the bonding properties of the IBTS, GO-IBTS, and ettringite interface are derived from the amphiphilic nature of IBTS, which can only produce unilateral bonding with ettringite, thus becoming a weak link in interface dissociation. The double-sided nature of GO functional groups enables GO-IBTS to interact well with bilateral ettringite, thus enhancing the interface-bonding properties.

17.
Front Public Health ; 11: 1121888, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37181719

RESUMO

Introduction: Chlamydia trachomatis is one of the most common bacterial sexually transmitted infections worldwide, and is associated with an increased risk of adverse pregnancy outcomes. However, whether providing chlamydia screening and treatment during the first trimester of pregnancy could reduce adverse pregnancy outcomes is still not clear. This study reports a randomized controlled trial (RCT) protocol to evaluate the effectiveness of chlamydia Test and Treat during early pregnancy in preventing adverse pregnancy outcomes in China. Methods and analysis: This trial is a multi-center two-arm RCT targeting 7,500 pregnant women in early pregnancy (6-20 weeks). The inclusion criteria included: 18-39 years old, on their first antenatal visit, in the first trimester, and plan to deliver in the study cities. Following a block randomization procedure, every block of twenty women will be randomly assigned in a 1:1 ratio into two arms: (1) a Test and Treat arm in which women receive free chlamydia testing immediately after enrollment and people tested as chlamydia positive will receive standardized treatment and partner treatment; (2) a control arm in which women receive regular prenatal care without receiving testing during the pregnancy period, but collect urine samples and test them after delivery or indicating a chlamydia-related complication during pregnancy happens. The primary outcome is a composite of eight adverse events rate at delivery between two arms, including stillbirth, infant death, spontaneous abortion, preterm labor, low birth weight, premature rupture of membranes, postpartum endometritis, and ectopic pregnancy. Secondary outcomes include the cost-effectiveness of the intervention, the proportion of people tested with chlamydia infection, the proportion of tested-positive patients that received treatment, and the proportion of people who were cured 1 month after the treatment initiation. Urine specimens will be collected and tested for chlamydia by using Nucleic Acid Amplification Test. Data will be analyzed according to the intention-to-treat principle. Discussion: This trial will test the hypothesis that early testing and treating of chlamydia can reduce the risk for adverse pregnancy outcomes and may help in developing chlamydia screening guidelines in China and other countries with a similar prevalence of chlamydia infection. Trial registration: Chinese Clinical Trials Registry, ChiCTR2000031549. Registered on April 4, 2020.


Assuntos
Aborto Espontâneo , Infecções por Chlamydia , Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Humanos , Adolescente , Adulto Jovem , Adulto , Resultado da Gravidez , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/prevenção & controle , Chlamydia trachomatis , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Ann Clin Microbiol Antimicrob ; 22(1): 39, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37198645

RESUMO

BACKGROUND: Antimicrobial resistance (AMR) of untreatable gonococcal infection is an emerging threat, especially in Guangdong, a prosperous province in Southern China. METHODS: N.gonorrhoeae was isolated from 20 cities in Guangdong and determined antimicrobial susceptibility. Through whole-genome sequencing (WGS), multilocus sequence typing (MLST), N.gonorrhoeae multiantigen sequence typing (NG-MAST), and N.gonorrhoeae sequence typing for antimicrobial resistance (NG-STAR) were obtained based on the PubMLST database ( https://pubmlst.org/ ). Phylogenetic analysis was used for dissemination and tracking analysis. RESULTS: Antimicrobial susceptibility was performed on 347 isolates, and 50 isolates were identified as decreased susceptibility (DS) to cephalosporins. Of which 16.0% (8/50) were ceftriaxone DS, 38.0% (19/50) were cefixime DS, and 46.0% (23/50) were both ceftriaxone and cefixime DS. In all, the dual-resistant rate of the cephalosporin-DS isolates was 96.0% for penicillin and 98.0% for tetracycline-resistant, and 10.0% (5/50) were resistant to azithromycin. All cephalosporin-DS isolates were resistant to ciprofloxacin but sensitive to spectinomycin. The predominant MLSTs were ST7363 (16%, 8/50), ST1903 (14%, 7/50), ST1901 (12%, 6/50), and ST7365 (10%, 5/50). Besides some isolates that failed genotyping (NA), NG-STAR ST1143 (n = 6) and NG-MAST ST17748 (n = 4) were the most prevalent. Twelve isolates with mosaic penA-60.001 allele retained the most elevated cephalosporin MIC (Minimum Inhibitory Concentration). Phylogenetic analysis revealed that epidemic penA-60.001 clones, either domestic or foreign, had spread to nine cities in Guangdong, and 9/12 clones were from the Pearl River Delta region. CONCLUSIONS: N. gonorrhoeae with cephalosporins-DS was extensively disseminated in Guangdong, Southern China, requiring strict surveillance.


Assuntos
Cefalosporinas , Gonorreia , Humanos , Cefalosporinas/farmacologia , Neisseria gonorrhoeae/genética , Ceftriaxona/farmacologia , Cefixima/farmacologia , Tipagem de Sequências Multilocus , Filogenia , Cidades , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Gonorreia/epidemiologia , Gonorreia/tratamento farmacológico , Testes de Sensibilidade Microbiana
19.
Med Mycol ; 61(4)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36931899

RESUMO

Genome-wide comparisons have shown Talaromyces marneffei possessed a stable mating type locus in its meiosis genes. But the function of the mating type locus in T. marneffei is not clear. The potential sex recombination might lead to problems in clinical, such as the evolution of increased resistance to antifungal drugs and virulence. To determine the mating type in a sample of 107 T. marneffei isolates and to explore the possible relationship between fungus virulence and mating type or source. We used PCR analysis to determine the distribution of mating type genes and also analyzed the relationship between mating type and isolated sources (including HIV-positive patients, HIV-negative patients, bamboo rats, and the environment). Further, the Drosophila melanogaster model of infection was used to compare the differences of virulence in mating type and sources. Our results showed the entire sample population of T. marneffei with an overabundance of MAT1-2 alleles, but with a higher ratio of MAT1-1 in the isolates from HIV-negative patients. However, no significant differences in the survival of the D. melanogaster infected neither with MAT1-1 (6.5 days) nor MAT1-2 (4 days) isolates. Similar results were also observed in virulence analysis tested with different sources of isolates. So, we found that all isolates bore single mating type idiomorphs and unequal distribution. The distribution of the MAT genes seems related to different sources. And the virulence differences are independent of mating type genotype and source.


Our work shows the entire sample population of 107 Talaromyces marneffei isolates with an overabundance of MAT1-2 alleles, but with a higher ratio of MAT1-1 in the isolates from HIV-negative patients. And fungus virulence is independent of mating type genotype and source in the Drosophila melanogaster model.


Assuntos
Infecções por HIV , Talaromyces , Animais , Drosophila melanogaster , Genes Fúngicos Tipo Acasalamento , Talaromyces/genética , Infecções por HIV/veterinária
20.
Cell Mol Neurobiol ; 43(6): 2925-2937, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36913114

RESUMO

Nerve tissue regeneration is a significant problem. After neural diseases and damage such as spinal cord injury (SCI), the accumulation of chondroitin sulfate proteoglycans (CSPG) comprising axonal inhibitory glycosaminoglycan chains in the microenvironment is a major barrier that obstructs nerve repair. Interfering with the production of glycosaminoglycans, especially the critical inhibitory chains, could be a potential therapeutic strategy for SCI, which is, however, poorly defined. This study identifies Chst15, the chondroitin sulfotransferase controlling the generation of axonal inhibitory chondroitin sulfate-E, as a therapeutic target of SCI. Using a recently reported small molecular Chst15 inhibitor, this study investigates the effects of Chst15 inhibition on astrocyte behaviors and the associated consequences of in vivo disruption of the inhibitory microenvironment. Deposition of CSPGs in the extracellular matrix and migration of astrocytes are both significantly impaired by Chst15 inhibition. Administration of the inhibitor in transected spinal cord tissues of rats effectively promotes motor functional restoration and nerve tissue regeneration by a mechanism related to the attenuation of inhibitory CSPGs, glial scar formation and inflammatory responses. This study highlights the role of Chst15 in the CSPG-mediated inhibition of neural recovery after SCI and proposes an effective neuroregenerative therapeutic strategy that uses Chst15 as a potential target.


Assuntos
Astrócitos , Traumatismos da Medula Espinal , Ratos , Animais , Proteoglicanas de Sulfatos de Condroitina , Traumatismos da Medula Espinal/tratamento farmacológico , Axônios , Medula Espinal , Regeneração Nervosa
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